Rust preventive compositions containing heterocyclic ketone condensates of acyclic succinic acids



Utecl States Patent RUST PREVENTIVE COMPOSITIONS CONTAININ IETEROCYCLICKETONE CONDENSATES OF ACYCLIC SUCCINIC ACIDS Donald D. Staker, Nitro, W.'Va., assignor to Monsanto Chemical Company, St. Louis, M0,, acorporation of Delaware No Drawing.

No. 678,432. Divided and this application May.26, 1959, Ser. No. 819,528I f;

8 Claims. (Cl. 252- 515) The present invention relates to newcompositions of matter and also to mineral oil compositions containingthe new products. The compositions comprising the present invention areformed by the reaction, aslater set forth in specific examples, of analkyl or alkenyl succinic acid or anhydride wherein the alkyl or alkenylgroup contains from 8 to 15 carbon atoms with a heterocyclic ketocompound, for example a lactam such as gamma-butyrolactam(2-pyrrolidinone), .gammavalerolactam (-methyl-2-pyrrolidinone),N-methyl pyrrolidinone, 2-piperidone, S-methyl 2'-piperi done, 3-ethyl-2-piperidone, 3-propyl 2-piperidone,roxindole and dioxindole, or alactone, as for example butyrolactone. The new compositions are oilsoluble, particularly in petroleum oil fractions, and have been found toexhibit rust preventive properties towards metals, especially steel-andferrous iron st r-faces.- The simplest and most convenient method ofdeveloping a rust preventing film on a metal surface is to dissolve.oneof the preferred class of rust preventive compounds disclosedhereinin a suitable petroleum base carrier such as a motongasoline, aviationgasoline, jet fuel, turbine oil. and .the like. Inasmuch as the leadsalts of compounds of the herein preferred class; of compounds do notform, or if formed are completely soluble in the petroleum fractionemployed, the compounds hereinafter described may be used in tetraethyllead treated fuels. Moreover,. the alkaline earth salts of the preferredclass ofv compounds either do not form when contacted with sea water orare soluble in hydrocarbons, thereby permitting the 'use of sea waterbalas-t in storage tanks earlier loaded with an oil fraction or fueltreated withcnerof the preferred rust preventive compounds. m I

Since the structure of the newrjcompounds is not known with certainty,theycan be described only as reaction products but the invention can bereadily. under-, stood from the description that follows as examples ofthe formation of the compounds and-their use .as rust p-reventives. 1

EXAMPLE 1.1-PRODllCT A Into a vessel provided with a stirrer, condenserand temperature recording means, therewere added 131.5 parts ofdodecenyl succinicanhydrideand 42.5 parts of '2-pyrrolidinone(gamma-butyrolactam); The anhydride was obtained from propylene polymerand maleic anhydride and may also be called tetrapropenylisuccinicanhydride. The agitated mixture was" then heated between 110-116" C. fora' period of several hours' and the neutralization numberdeterminedfrorn time to time on samples withdrawn from the reaction.Since'there was no change in this value for a 5 hour period, the heatingwas discontinued after an overall heating time of 8 /2 hours to obtainaproduct with a neutralization number of 236. The course of the reactionis unknown but probably involves splitting both the lactam and anhydriderings to form an amide. However, a neutralization number of 320 is thecalculated-value for the mixed an- Original application Aug. 15, 1957,Serf.

hydrideamide which would be formed by splitting the 2-pyrrolidinonejring between-the nitrogen and the carbonyl, the nitrogen forming anamide and the carbonyl reforming an anhydride linkage by uniting withthe acid radical liberated from the succinic anhydride. The

product was completely soluble in concentrations of 1% and 5% inpetroleum ether and formed bright solutions in both instances. 1

EXAMPLE 2. PnoDUcT B EXAMPLE 3.VPRIODUCT c 1 Example 1 above wasduplicated except that 9 parts of water were added to the originalcharge and heating ciarrledout at 95-98 C. for'4% hours. A productpossessing a neutralization numberof 286 was obtained as compared withavalue of 304 calculated for simple acid hydrolysis/of the lactam toyield an amide containing two carbonylgroups.

EXAMPLE: 4.PRODUCT D Into the same type equipment employed in Example '1was charged 1315 parts of dodecenyl succinic anhydride, .430 partsofg-butyrolactone and 2.0 parts of "of the reaction product to 100 partsby weight of petroe i t'riethyla'm'ine'. The chargewas heated for 3hours at 110-120? C. at which time the neutralization number was 274..Heating was continued for an hour and 38 minutes longer and since theneutralization number remained constant, heating was discontinued. Theproduct was completely soluble at 5% concentration inpetroleum ether." f

EXAMPLE 5'.-+PROD UCI E In'to the same type equipment employed inExample 1 was charged 133 parts of dodecenyl succinic anhydride, 43parts of butyrolactone and9 parts 'of water. Thecharge heated .at97-100? C. for about 13 hours at'which time the neutralization numberwas '302 and the product completely soluble in petroleum ether at 5%concentration.

, 'The application of the products of the present invention as rustinhibitorswas determined'by a series of tests.' 'Iheva'riousproductswere tested to determine their solubility in'petroleum oil by adding 1%weight leum 'etherand stirring. jlf any residue be observed, the productisindicated' asv insoluble. The rust preventive properties of thechemical products were observed by carefullyclea'ninga'nd polishing, inthe well recognized manner for performingthis test, strips of steel 3%"x x fid'having an S.A.E. grade designation of 1020 and vigorouslyshaking each specimen in "cc. of petroleurn ether containing the desiredconcentration or con: centrations (from ,5 to 20 parts per million ofsolvent) "of the rust inhibitor. After standing for one-half hour, 2 cc.Iof distilledwatcrwere added and the sample 're'shaken. The strip wasallowed to stand in the wet petroleum ether at'room temperature forabout 3 hours nd was then removed and visually inspected for rust. heresults of the tests with typical members of the new lass of reactionproducts are set forth in the following able:

Table I Solubility in Steel Strip Rust Test Product Petroleum Ether 20ppm. p.p.m. 5 p.p.m.

.. complete Various other tests utilized in the art were also emaloyedin the further testing of chemical products of he present invention. Adescription of such tests and he results obtained therefrom follow.

Water tolerance test, A.S.T.M. 1094-53.This test is ised to evaluate theemulsion characteristics of the rust uhibited petroleum fraction, suchas a petroleum fuel. The apparatus consists of a 100 cc. glass stopperedgradlated cylinder, which after thorough cleaning is rinsed horoughlywith distilled water and stored completely full tf distilled water untilused in a test. The water is rerioved and 80 cc. of iso-octanecontaining parts per uillion of the inhibitor under test is placed inthe graduite and 20 cc. of distilled water added thereto and the nixtureis shaken vigorously at room temperature for 2 minutes. The mixture isthen allowed to stand on a Iibration-free surface for 5 minuteswhereupon the volune of the aqueous layer and the amount of emulsion, ifmy, are recorded. In order to pass the test, the fuel shall ieparatesharply from the water and there shall be no evidence of an emulsion,precipitate or suspended mat- 161 within or upon either layer. Neitherlayer shall have :hanged more than 1 cc. in volume.

Sea water reaction test.This test is designed to dezermine thesolubility of the alkaline earth salts of rust inhibitors. Synthetic seawater was'prepared according :o the method set forth in Procedure B,A.S.T.M. D 665- 53T. The method consists in adding 250 cc. of n-hep tanecontaining about 200 ppm. of the material to be tested and ccofsynthetic sea water to a 500 cc. 3- neck flask equipped with stirrer andreflux condenser and stirring for minutes at room temperature. Agitationwas stopped and when motion had ceased the interface was examined forscum and the walls of the flask examined for precipitate of which thereshall be none.

Lead salt test.--This test is designed to indicate the possibility ofprecipitate from the use of rust inhibitor in a leaded gasoline. In thistest, an ionizable lead salt is added to assure a concentrationof leadion. The test solution is prepared by dissolving 25 parts of leadnaphthenate in 2500 parts of a regular gasoline and the solution isfiltered through a double thicknessof filter paper and then through alayer of fullers earth. Thereupon 100 cc. of the test solution is addedto a 500 3-neck Flask equipped with a stirrer and air condenser.Agitation is started and the rust inhibitor under test isadded dropwiseuntil about 0.5 gram has been added whereupon agitation is continued foran hour at room temperature and the mixture is examined for haziness orinsolubles with the aid of a flashlight. To pass the test ther e shallbe no more haze than is exhibited by use of a blank test with noinhibitor present.

The rust preventing characteristics of a steam turbine oil containing aproduct of the present invention inthe presence of water was determinedby following A.S.T.M. Test D 665-53T, Procedure B thereof. The oilemployed was a base stock in commercial use for the formulating of steamturbine finished lubricants and, of course, contained no inhibitor ofany kind. In this test and the other tests described above, variousreaction products "of an 4 alkenyl succinic anhydride yielded theresults shown below in Table II. V i

Table II Solubility Sea Water Lead inPetro- Water Toler- Salt Productleum Rust Test fIest ance Test Ether complete..-

The results of the several tests clearly show that the new reactionproducts of the class described are oil soluble, are effective inprotecting ferrous iron and steel against'rusting in oil-water contactand do not form continuous oil-water emulsions. 7

It is intended to cover all changes and modifications of the examples ofthe invention chosen for purposes of disclosure which do not constitutedepartures from the spirit and scope of the invention.

This application is a division of Serial No. 678,432, filed August 15,1957.

What is claimed is:

1. A rust preventive composition comprising a major gzroportion of aliquid petroleum hydrocarbon carrier and a minor proportion suflicientto inhibit rusting of a reaction product obtained by heating at -120 C.equal molar proportions of a member of the group consisting ofZ-pyrrolidinone, S methy1-2-pyrrolidinone, N-methylpyrrolidinone,.2-piperidone, 3-methyl-2-piperidone, 3- ethyl-2-piperidone,3-propyl-2-piperidone, oxindole, dioxindole and butyrolactone with amember of a group consisting of alkenyl succinic anhydrides and alkenylsuccinie acids, the alkenyl radical containing 8-15 carbon atoms.

2. A rust preventive composition comprising a major proportion of apetroleum fuel and a minor proportion suificient to inhibit rusting of areaction product obtained byheating at 95-120 C. equal molar proportionsof a member of the group consisting of 2-pyrrolidinone, 5-miethyl-Z-pyrrolidinone, N-methylpyrrolidinone, 2-piperidone,3-methyl-2-piperidone, 3-ethyl-2-piperidone, 3- propyl-Z-piperidone,oXindole, dioxindole and butyrolactone with a member of a groupconsisting of alkenyl succinic anhydrides and alkenyl succinic acids,the alkenyl radical containing 8-15 carbon atoms.

3. A rust preventive composition comprising a major proportion of amineral oil lubricating fraction and a minor proportion suflicient toinhibit rusting of a reaction product obtained by heating at 95120 C.equal molar proportions of a member of the group consisting of2-pyr'rolidinone, 5-methyl-2-pyrrolidinone, N methylpyrrolidinone,2-piperidone, 3-methyl-2-piperidone, 3-ethyl- 2-piperidone,3-propyl-2epiperidone, oxindole, dioxindole and butyrolactone'with amember of a group consisting of alkenyl succinic anhydrides and alkenylsuccinic-acids, the alkenyl radical containing 8-15 carbon atoms.

4. Artist preventive composition comprising a major proportion of aliquid petroleum hydrocarbon carrier having dissolved therein a minorproportion sufl'icient to inhibit rustingof a reaction product obtainedby heating at 95-120 C. equal molar proportions of N-methyl 2-p'yrrolidinone and branched chain dodecenyl succinic acid.

5. A rust preventive composition comprising a major proportion of aliquid petroleum hydrocarbon carrier having dissolved therein a minorproportion suflicient to inhibit rusting of a reaction product obtainedby heating at 95-120 C. equal molar proportions of 2-pyrrolidinone andbranched chain dodecenyl succinic anhydride.

'6. A rust preventive composition comprising amajor proportion of,aliquid petroleum hydrocarbon carrier having dissolved therein a minorproportion sufiicient to inhibit rusting of a reaction product obtainedby heating at 95-120 C. equal molar proportions of 2-pyrrolidinone andbranched chain dodecenyl succinic acid. a

7. A rust preventive composition comprising a major proportion of aliquid petroleum hydrocarboncarrier having dissolved therein a minorproportion suflicient to inhibit rusting of a reaction product obtainedby heating 7 6 having dissolved therein a minor proportion sufiicient toinhibit rusting of a reaction product obtained by heating at 95-120" C.equal molar proportions of butyrolactone and branched chain dodecenylsuccinic anhydride.

References Cited in the file of this patent UNITED STATES PATENTSRocchini July 22, 1952 OTHER REFERENCES Shpitalnyi et al., Chem. Abs.47, 341 (1953).

1. A RUST PREVENTIVE COMPOSITION COMPRISING A MAJOR PROPORTION OF ALIQUID PETROLEUM HYDROCARBON CARRIER AND A MINOR PROPORTION SUFFICIENTTO INHIBIT RUSTING OF A REACTION PRODUCT OBTAINED BY HEATING AT95-120*C. EQUAL MOLAR PROPORTIONS OF A MEMBER OF THE GROUP CONSISTING OF2-PYRROLIDINONE, 5-METHYL-2-PYRROLIDINONE, N-METHYLPYRROLIDINONE,2-PIPERIDONE, 3-METHYL-2-PIPERIDONE, 3ETHYL-2-PIPERIDONE,3-PROPYL-2-PIPERIDONE, OXINDOLE, DIOXINDOLE AND BUTYROLACTONE WITH AMEMBER OF A GROUP CONSISTING OF ALKENYL SUCCINIC ANHYDRIDES AND ALKENYLSUCCINIC ACIDS, THE ALKENYL RADICAL CONTAINING 8-15 CARBON ATOMS.